Please I know it's a little embarrassing to ask but I couldn't solve this one,I need help .I was asked to prepare a 10 mM 500 ml tris-HCl buffer at pH 7.5 . Pkb=8.3 and MW of tris is 121.1 .I know I need to use Henderson-Hasselbalch equation but I'm not good with it and somehow I got confused.can anyone explain me how to calculate exact values,not in pratic way but in the theoretical way ?